I remember this story of the Queen mother´s two nieces when it first broke in the British newspapers, it was called a great scandal.
Unfortunately it was the way mental illness was often treated in those days.
The families would rather forget that these unfortunate members existed.

Prince John was not mentally retarded, I heard an interview with a lady who had played with him as a child and his only problem was epilepsy and he was kept separate from his siblings on the advice of his family doctor, but they were all very fond of him and he was always referred to as dear little Johnny The lady said he was a sweet boy and she had postcards sent to her when he was away on holiday and they were very well written and signed by him. .
Poor boy, it was a illness misunderstood and in the end, he died young.

What a load of nonsense. It always amazes me that these people show up even though science is much more sophisticated and can easily prove one is a fraud. The best thing is that moreover, most of the time science isn't needed because, as this musician has shown, his story makes absolutely no sense when compared to the facts of those supposedly involved. If this man is the King's son, I'm King Harald's daughter. I'm most certainly NOT!!! Seriously, people who put out these theories have got to have some sort of psychiatric problem and they usually do plus a need to have attention to themselves.

if paul got his wish that still doesn't make him a Prince of Roumania. I have never understood how Lambrino had the Temerity, if King Ferdinand as decreed the marriage null and void, it was against the Constitution of the time and the House Laws, and HM King Michael upheld those rulings, I mean the King is the Fountain on Honour. The Sole Arbiter .
You think he wants some of Carols fortune? I read somewhere that even King Michael couldn't access what was still in Carol's name b/c he didn't have the password to the Bank Account??